Mechanical difficulty vs Strategic difficulty
By Clockwork
I thought I'd write an article about game design, here specifically is an article on a concept which everyone uses in every game. A game, any game, is essentially a challenge asking 'Can you x?' Mechanical difficulty for the purpose of this article is determined by the number of actions that are available to the player whereas strategic difficulty is the number of options (decisions) to consider when choosing those mechanical actions.
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Chess: High Mechanical AND Strategic Difficulty!
An example of a game with low mechanical difficulty and high strategic difficulty is the tabletop game Diplomacy; there are a total of three different moves: attack with army x to region y, support army x with army z and hold. You'll be moving fewer pieces than you can count on one hand but through complexity of strategy each of these moves will be made with respect to a great number of things and then exponentially increased by the number of opposing players past 1. Not that you'd want to play 1v1 Diplomacy, that would be super boring.
On the flip side; Exploding Kittens has a lot of different cards which can be played that do a lot of different things and learning what they do in combination with each other creates this complexity of mechanics. There are 8 different cards which do wacky, crazy, kooky things as well as neutral cards which don't do anything other than serve as a bluff for having the other 8 types of cards. It sounds like there's room for decision making but there are no informed decisions to be made because there is no way to gather knowledge on opponents' hands and winning doesn't require any combination of cards to collect through the game.
The majority of the time, games will have some midway combination of strategy and mechanics, for example a game with high mechanical and strategic difficulty would be Chess - there are 6 pieces doing different things and each turn there are a huge number of potential plays, on the first turn for example there are 20 (according to my sketchy, conflicting, research) and 400 different positions after each player makes one move.
So, how does this help design? It'll happen naturally of course during creation but being aware of which way your game leans can influence how to market it and the types of gamers (more importantly, where to find them) you'll be catering to. The ability to critically look at your game and see - this is a decision the player is making vs the player has so many options here with the nuance that entails can shift the balance to being easier to understand or more complex.